The present invention relates generally to a rolling mill roll assembly and more particularly to an assembly of this type having a removable outer sleeve shrink-mounted on an inner mandrel.
A rolling mill roll assembly is typically utilized in the rolling of metals such as steel. Such an assembly may comprise a cylindrical inner mandrel upon which is shrink-mounted a cylindrical outer sleeve. Examples of a rolling mill assembly of this type and of the procedure for shrink mounting or fitting the sleeve on the mandrel are disclosed in Samuels, et al. U.S. Pat. No. 2,964,251, and the disclosure thereof is incorporated herein by reference.
In a shrink mounting procedure of the type described in the Samuels et al. patent, the sleeve is initially provided with an inner diameter slightly smaller than the outer diameter of the mandrel. The sleeve is then heated to thermally expand the inner diameter to a dimension greater than that of the outer diameter of the mandrel following which the sleeve is slipped around the mandrel, or the mandrel is inserted into the sleeve, and the sleeve is allowed to cool thereby causing it to contract or shrink to tightly bind the sleeve onto the mandrel. Because, in a cooled condition, the sleeve has an inner diameter slightly smaller than the outer diameter of the mandrel, shrink fitting of the sleeve around the mandrel in the manner described above will cause hoop stresses in the sleeve, and that is undesirable.
Recently, it has been proposed to bind the sleeve to the mandrel with an adhesive or glue. In such an approach, the sleeve could be provided with an initial inner diameter which is essentially the same as the outside diameter of the mandrel. To facilitate fitting this sleeve on the mandrel, the sleeve is heated to thermally expand its inside diameter following which it is slipped around the mandrel which has been coated with adhesive, and the sleeve is allowed to cool thereby causing it to contract and become bound to the mandrel through the medium of the adhesive. This approach probably avoids the hoop stresses which occur when the sleeve is bound to the mandrel by shrink fitting, but it creates other problems. These include centering the sleeve around the mandrel as the sleeve undergoes contraction during cooling, and preventing the adhesive from being squeezed out from between the sleeve and the mandrel during contraction of the sleeve.